NetworkViewNetworkView is a compact network discovery and management tool for the Win32 platform : in a few minutes, it will discover all TCP/IP nodes and draw a full graphical map (including routes) using DNS, MAC addresses, SNMP and TCP Ports information.

PRTG - Paessler Router Traffic GrapherWith PRTG you can easily set up and run a monitoring station that logs the amount of data flowing out and into any SNMP enabled network component. The most common usage is monitoring the bandwidth usage of leased lines, routers and firewalls.

DEKSI Network MonitorDEKSI Network Monitor is an advanced, powerful, and feature rich tool that monitors servers located on your LAN, WAN, and the Internet. Windows 9X, NT, 2000, XP, 2003 Server compatible and can monitor the servers with any operating system.

Engineers EditionAn arsenal of over 40 Networking Tools. Includes Bandwidth Monitoring, Network Discovery, Switch Port Mapping, Cisco Router tools, Performance Tools, Fault Management, a MIB Browser & much more. As you can see from its size, this toolset is LOADED.